If you have a newer nvidia card, you can still use the physx effects, though. If you delete/move the packed physx libraries in the Mirror's Edge folder. When you do that, the game will use the physx library packed with the display driver instead.

The one that comes with the game is an old version, and it doesn't work with the kepler and optimus cards.. possibly other cards too, that allow the cpu to partially run physx.

So rename or move physxcore.dll, physxdevice.dll, and the physxlocal folder. (Leave the other physx* files alone.)

If you have a newer nvidia card, you can still use the physx effects, though. If you delete/move the packed physx libraries in the Mirror's Edge folder. When you do that, the game will use the physx library packed with the display driver instead.

The one that comes with the game is an old version, and it doesn't work with the kepler and optimus cards.. possibly other cards too, that allow the cpu to partially run physx.

So rename or move physxcore.dll, physxdevice.dll, and the physxlocal folder. (Leave the other physx* files alone.)

Yeah, I forgot to mention that, thanks

Game can still get laggy though - try taking out every banner in the open area at the end of chapter 1.

The game uses PhysX, which is a physics bound side engine built for Nvidia's main GPU series, the GTX. Most time it is enabled because the game will either: A) Rely on physics or B) Optimized for Nvidia

PhysX is actually always on being the physics engine that comes with the Unreal engine (not that a developer can't choose to use something else). The toggle turns on the extras: persistent glass shards, deformable fabrics, various other bits of eye-candy etc. that require extra resources to process. Because not everyone will have a powerful rig capable of this, it is put into an extra setting. As such, these effects can't be relied on for controlling the game, so you get effects like the spreading corrosion in borderlands 2 being a simple range based solution, whether you can see the corrosion dripping down the hill or not.

PhysX is actually always on being the physics engine that comes with the Unreal engine (not that a developer can't choose to use something else). The toggle turns on the extras: persistent glass shards, deformable fabrics, various other bits of eye-candy etc. that require extra resources to process. Because not everyone will have a powerful rig capable of this, it is put into an extra setting. As such, these effects can't be relied on for controlling the game, so you get effects like the spreading corrosion in borderlands 2 being a simple range based solution, whether you can see the corrosion dripping down the hill or not.

Acctually the PhysX implementaion in this game is horrible causing the lag on even higher end PC's. I can run most games with PhysX on, but not this one.